To determine the NH₄⁺-N release from polluted river channel sediments,water and sediment samples were collected.We examined sedimentary NH₄⁺-N release under two aeration conditions: aerating to water (EW) and aerating to sediments (ES).The experimental results showed that the effect of NH₄⁺-N removal in ES was higher than that in EW,which removed the NH₄⁺-N both from pore water and sediments.In the ES group,the concentrations of NH₄⁺-N in sediment and pore water were decreased by 63.39% and 43.33%,respectively.However,the values of NH₄⁺-N in sediments and pore water were merely decreased by 7.54% and 13.98%,respectively,in the EW group.The variation of the diffusion flux of NH₄⁺-N was similar between the control group and the EW group across the sediment-water interface,with the value of the EW higher than that of the control group.The diffusion flux of NH₄⁺-N in the ES group was completely different from the other two groups.Throughout the trial period(other than section 5 d),the value of flux in the ES group was lower than that in the EW group,and the lowest concentration was showed up in the first 15 d.The value was 13.73 mg/(m²·d),which just accounted for 14.68% in the EW group and 19.93% in the control group,respectively.Our results indicated that the NH₄⁺-N in the cores of sediment aeration group had a lower release potential than that in the cores of water aeration group.